lightning/tests/trainer/test_training_loop.py

211 lines
6.8 KiB
Python

# Copyright The PyTorch Lightning team.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import torch
from pytorch_lightning import seed_everything, Trainer
from tests.helpers import BoringModel
def test_training_loop_hook_call_order(tmpdir):
"""Tests that hooks / methods called in the training loop are in the correct order as detailed in the docs:
https://pytorch-lightning.readthedocs.io/en/latest/common/lightning_module.html#hooks"""
class HookedModel(BoringModel):
def __init__(self):
super().__init__()
self.called = []
def on_epoch_start(self):
self.called.append("on_epoch_start")
super().on_epoch_start()
def on_train_epoch_start(self):
self.called.append("on_train_epoch_start")
super().on_train_epoch_start()
def on_train_batch_start(self, batch, batch_idx, dataloader_idx):
self.called.append("on_train_batch_start")
super().on_train_batch_start(batch, batch_idx, dataloader_idx)
def training_step(self, batch, batch_idx):
self.called.append("training_step")
return super().training_step(batch, batch_idx)
def on_before_zero_grad(self, optimizer):
self.called.append("on_before_zero_grad")
super().on_before_zero_grad(optimizer)
def optimizer_zero_grad(self, epoch, batch_idx, optimizer, optimizer_idx):
self.called.append("optimizer_zero_grad")
super().optimizer_zero_grad(epoch, batch_idx, optimizer, optimizer_idx)
def backward(self, loss, optimizer, optimizer_idx, *args, **kwargs):
self.called.append("backward")
super().backward(loss, optimizer, optimizer_idx, *args, **kwargs)
def on_after_backward(self):
self.called.append("on_after_backward")
super().on_after_backward()
def optimizer_step(
self,
epoch,
batch_idx,
optimizer,
optimizer_idx,
optimizer_closure,
on_tpu,
using_native_amp,
using_lbfgs,
):
super().optimizer_step(
epoch, batch_idx, optimizer, optimizer_idx, optimizer_closure, on_tpu, using_native_amp, using_lbfgs
)
self.called.append("optimizer_step") # append after as closure calls other methods
def on_train_batch_end(self, outputs, batch, batch_idx, dataloader_idx):
self.called.append("on_train_batch_end")
super().on_train_batch_end(outputs, batch, batch_idx, dataloader_idx)
def training_epoch_end(self, outputs):
self.called.append("training_epoch_end")
super().training_epoch_end(outputs)
def on_train_epoch_end(self, outputs):
self.called.append("on_train_epoch_end")
super().on_train_epoch_end(outputs)
def on_epoch_end(self):
self.called.append("on_epoch_end")
super().on_epoch_end()
model = HookedModel()
# fit model
trainer = Trainer(
default_root_dir=tmpdir,
max_epochs=1,
limit_val_batches=1,
limit_train_batches=1,
limit_test_batches=1,
progress_bar_refresh_rate=0,
weights_summary=None,
)
assert model.called == []
trainer.fit(model)
expected = [
"on_epoch_start", # validation
"on_epoch_end",
"on_epoch_start", # training
"on_train_epoch_start",
"on_train_batch_start",
"training_step",
"on_before_zero_grad",
"optimizer_zero_grad",
"backward",
"on_after_backward",
"optimizer_step",
"on_train_batch_end",
"training_epoch_end",
"on_train_epoch_end",
"on_epoch_end",
"on_epoch_start", # validation
"on_epoch_end",
]
assert model.called == expected
def test_outputs_format(tmpdir):
"""Tests that outputs objects passed to model hooks and methods are consistent and in the correct format."""
class HookedModel(BoringModel):
def training_step(self, batch, batch_idx):
output = super().training_step(batch, batch_idx)
self.log("foo", 123)
output["foo"] = 123
return output
@staticmethod
def _check_output(output):
assert "loss" in output
assert "foo" in output
assert output["foo"] == 123
def on_train_batch_end(self, outputs, batch, batch_idx, dataloader_idx):
HookedModel._check_output(outputs)
super().on_train_batch_end(outputs, batch, batch_idx, dataloader_idx)
def training_epoch_end(self, outputs):
assert len(outputs) == 2
[HookedModel._check_output(output) for output in outputs]
super().training_epoch_end(outputs)
def on_train_epoch_end(self, outputs):
assert len(outputs) == 2
[HookedModel._check_output(output) for output in outputs]
super().on_train_epoch_end(outputs)
model = HookedModel()
# fit model
trainer = Trainer(
default_root_dir=tmpdir,
max_epochs=1,
limit_val_batches=1,
limit_train_batches=2,
limit_test_batches=1,
progress_bar_refresh_rate=0,
weights_summary=None,
)
result = trainer.fit(model)
assert result == 1, "Training did not complete"
def test_training_starts_with_seed(tmpdir):
""" Test that the training always starts with the same random state (when using seed_everything). """
class SeededModel(BoringModel):
def __init__(self):
super().__init__()
self.seen_batches = []
def training_step(self, batch, batch_idx):
self.seen_batches.append(batch.view(-1))
return super().training_step(batch, batch_idx)
def run_training(**trainer_kwargs):
model = SeededModel()
seed_everything(123)
trainer = Trainer(**trainer_kwargs)
trainer.fit(model)
return torch.cat(model.seen_batches)
sequence0 = run_training(
default_root_dir=tmpdir,
max_steps=2,
num_sanity_val_steps=0,
)
sequence1 = run_training(
default_root_dir=tmpdir,
max_steps=2,
num_sanity_val_steps=2,
)
assert torch.allclose(sequence0, sequence1)